Abertillery and Ebbw Vale Sports Centres have since opened their doors for washing and shower facilities for those who need them.

A Wales and West Utilities spokesman said: “We have been working to restore the gas supply to approximately 755 properties in the Nantyglo area, which has been interrupted by water from a burst water main in Waun Heulog getting into our gas pipe.

“Our engineers have visited every property affected to make sure the gas supply is turned off, and are now working to remove the water from the gas pipe.

“Once this is completed we will be visiting each property again to safely turn their gas supplies back on.

“We are working round the clock to resolve this issue. We are as yet unable to give an exact time when gas supplies will be restored. This is a complex operation that may take several days to complete.

“Gas supplies will not all be restored at the same time, but we will keep people updated as to how we are progressing with this.”

According to a spokesman, about 50 engineers are working to fix the problem. Initially it was reported the number of homes affected was 500. That number has increased following a recount but Wales and West Utilities have said the problem is not spreading.

Nantyglo councillor John Mason has no central heating and cannot use his gas cooker as a result of the disrupted supply. He does have hot water though thanks to an immersion heater. Electrical fans have been brought in for warmth.

He said the housing association Tai Calon have made arrangements to use the Winchestown Pensioners’ Hall as a focal point for people to ask questions.

Wales and West Utilities said it has distributed 85 fan heaters and 82 hot plates for warming food to vulnerable customers.

Anyone who needs assistance should call its customer services team on 0800 912 2999.

Abertillery Sports Centre is open from 7am to 5pm on Saturday and from 8.30am to 5pm on Sunday. It will be closed on bank holiday Monday.

In Ebbw Vale, the sports centre is open from 8am to 4pm on Saturday, 8am to 8pm on Sunday and 8am to 4pm on bank holiday Monday.